JP2017527229A - Programmable stabilization network - Google Patents

Abstract

The present disclosure includes programmable stabilization circuits and methods. In one embodiment, a power amplifier in a wireless transmitter includes a transistor having a gate, a source, and a drain. The drain to gate feedback is dynamically modified to stabilize the amplifier under multiple changing operating conditions. In one embodiment, a series RC circuit is configured between the drain and gate, and the RC circuit value is adjusted based on different power supply voltage modes.

Description

Cross-reference of related applications

  [0001] This application claims priority to US Application No. 14 / 487,000 filed on September 15, 2014, the contents of which are hereby incorporated by reference in their entirety for all purposes. Is incorporated herein by reference.

  [0002] The present disclosure relates to electronic circuits and methods, and in particular to programmable stabilization circuits and methods.

  [0003] The widespread use of wireless technologies and standards places unprecedented high demands on electronic circuit technology. The circuit needs to be able to operate under significantly different operating conditions, and in some cases needs to be able to work well when the wireless system changes between various modes of operation. is there. The complexity of this dynamic environment is particularly challenging for analog amplifiers such as power amplifiers in wireless transmitters. The power amplifier may drive the antenna with, for example, sufficient output power to broadcast the signal to the receiving system. Thus, the power amplifier needs to maintain stability when the wireless transmitter changes operating conditions during transmission, for example.

  FIG. 1 illustrates an exemplary transistor device 110 used in the power amplifier circuit 100. One challenge with robust amplifier design is related to the structure and parasitic effects of the transistors used to amplify the signal in the transmission path. For example, some MOS transistor devices have very short gates to compensate for the high gate to drain capacitance (Cgd) 120 associated with some device structures. Can have a length. However, reducing the gate length can also make the amplifier unstable under certain conditions. As illustrated by this example, some transistor devices and circuits designed to be stable with respect to some operating conditions may be unstable with respect to other operating conditions. However, traditional designs that are stable under all operating conditions can be extremely inefficient in some situations, for example, resulting in wasted power.

  [0005] The present disclosure includes programmable stabilization circuits and methods. In one embodiment, a power amplifier in a wireless transmitter includes a transistor that includes a gate, a source, and a drain. The drain to gate feedback is dynamically modified to stabilize the amplifier under multiple varying operating conditions. In one embodiment, a series RC circuit is configured between the drain and gate, and the RC circuit value is adjusted based on different power supply voltage modes.

  [0006] The following detailed description and the accompanying drawings provide a further understanding of the nature and advantages of the present disclosure.

[0007] FIG. 1 illustrates a typical transistor device used in a power amplifier circuit. [0008] FIG. 2 illustrates a wireless transmitter including a power amplifier, according to one embodiment. [0009] FIG. 3 illustrates a wireless transmitter including a power amplifier, according to another embodiment. [0010] FIG. 4 illustrates a wireless transmitter including a power amplifier, according to yet another embodiment. [0011] FIG. 5A illustrates an exemplary programmable feedback circuit, according to one embodiment. [0012] FIG. 5B illustrates an exemplary programmable feedback circuit, according to another embodiment. [0013] FIG. 5C illustrates an exemplary programmable feedback circuit, according to yet another embodiment. [0014] FIG. 6A illustrates an exemplary programmable feedback circuit, according to another embodiment. [0015] FIG. 6B illustrates an exemplary programmable feedback circuit, according to yet another embodiment. [0016] FIG. 7 illustrates an exemplary transistor feedback circuit configuration, according to another embodiment.

Detailed description

  [0017] The present disclosure relates to programmable stabilization circuits and methods. In the following description, for purposes of explanation, numerous examples and specific details are set forth in order to provide a thorough understanding of the present disclosure. However, it is also noted that the present disclosure as set forth in the claims may include some or all of the features in these examples, either alone or in combination with other features described below. It will be apparent to those skilled in the art that further modifications and equivalents of the features and concepts may be included.

  [0018] FIG. 2 illustrates a wireless transmitter 200 that includes a power amplifier (PA) 210, according to one embodiment. The wireless transmitter 200 may be part of a wireless communication system that can send and receive information using RF signals (receiver not shown). The wireless transmitter 200 may include a baseband controller 201 for receiving digital information to be transmitted and control information for controlling the operation of the transmitter. For example, the transmitter 200 may operate in a variety of modes and may include a transmission (Tx) mode control circuit 202 for configuring the transmitter circuit to operate in different modes. The various modes may have different gain settings, power settings, or may be associated with different frequency bands and protocols, for example.

  The output of baseband controller 201 is coupled to the input of analog preprocessing block 203. Various embodiments of analog preprocessing may include, for example, digital-to-analog conversion, filtering, gain control, and / or modulation (upconversion) of data to be transmitted. The output of analog preprocessing 203 is coupled to the input of power amplifier 210 for amplifying input signal Vin and producing output signal Vout for driving antenna 250.

  [0020] The power amplifier 210 may include one or more gain stages comprising transistors. In this example, one gain stage is shown for illustrative purposes. In some embodiments, the gain stage can be at the output of a power amplifier where the drain of gain stage transistor 220 is coupled to antenna 250. In other embodiments, the gain stage may be an intermediate stage, where the drain is coupled to the antenna through one or more additional gain stages. In some embodiments, multiple gain stages within a power amplifier may include programmable feedback as described herein, for example. The transistors in each gain stage are typically powered by a power supply voltage Vdd. In certain applications, different operational modes may change the power supply voltage Vdd received by the power amplifier 210. Since Vdd can vary over time, it is sometimes denoted herein as Vdd (t). Exemplary modes that affect the power supply voltage Vdd are Average Power Tracking Mode (“APT mode”), envelope tracking (ET) mode (eg, where the power supply voltage is transmitted). Corresponding to the envelope of the signal to be done), or a low power mode (eg, where a constant Vdd is reduced for lower power transmission). The power supply voltage can also be used when using different wireless transmission protocols such as GSM®, WCDMA®, CDMA2000, or various LTE technologies including LTE® 5, LTE 10, and LTE 20, for example. May be affected by the transmission power required.

  [0021] Changes in output power and / or power supply voltage may create significantly different stability constraints for the power amplifier. Accordingly, features and advantages of the present disclosure include transistor device 220 in a gain stage having a programmable feedback circuit 221 configured between the drain and gate of transistor device 220. Programmable feedback circuit 221 has an input terminal coupled to the drain of transistor 220, an output terminal coupled to the gate of transistor 220, and a control input for receiving control signal Ctrl. Programmable feedback circuit 221 adjusts the series RC circuit between the gate and drain of transistor 220 based on a control signal received at the control input. For example, in certain embodiments, programmable feedback circuit 221 produces a first RC circuit value when wireless transmitter 200 is configured to produce a first power supply voltage to the drain of transistor 220. The programmable feedback circuit 221 changes the negative feedback from the drain to the gate of the transistor 220 when the wireless transmitter 200 is configured to produce different power supply voltages to the drain of the transistor 220. To generate another RC circuit value. For example, when different modes change the power supply voltage provided to the drain of transistor 220, control so that different feedback configurations from drain to gate can be programmed to maintain the stability and performance of the power amplifier. The signal may be based on the mode of operation of transmitter 200. To illustrate the advantages of the present disclosure, programmable feedback circuit 221 is configured such that transistor 220 when the wireless transmitter is configured to produce a variable power supply voltage that corresponds to the envelope of the input signal (eg, ET mode). The first RC circuit value may be created between the drain and the gate of the first RC circuit value. However, the programmable feedback circuit 220 is configured to generate a second RC circuit when the wireless transmitter is configured to produce a constant power supply voltage to the drain of the transistor (eg, APT mode). Can be configured to produce a value, where the second RC circuit value (eg, in APT mode), for example, increases negative feedback from drain to gate to improve stability during APT mode To be smaller than the first RC circuit value (eg, in ET mode).

  [0022] FIG. 3 illustrates a wireless transmitter including a power amplifier, according to one embodiment. In this example, the signal Si to be transmitted is provided to the preprocessor 302. A control circuit 301 (eg, baseband or other processor) may determine the mode of operation for the transmitter and may set the preprocessor 302. For example, in some operating conditions, the system may be configured to operate in a mode with a constant power supply voltage (eg, APT mode or low power mode). In this case, the power supply 323 can be configured to produce a constant Vdd. As another example, under other operating conditions, the system uses a variable power supply voltage, such as an envelope tracking (ET) mode in which the variable power supply voltage corresponds to the envelope of the input signal Vin of the power amplifier 310, for example. Can be configured to operate in the mode that was in effect. In this case, the control circuit 301 may set the preprocessor 302 to produce an envelope signal Ve to the power supply 323 and a corresponding input voltage Vin that is coupled to the input of the power amplifier 310 through the matching network 303 in this example. .

  [0023] In this illustrative example, power amplifier 310 includes a gate configured to receive input voltage Vin, a source coupled to ground, and a power supply voltage Vdd through an RF choke (RFC) 322. A transistor 320 having a drain coupled to receive (t). The output of the amplifier (eg, in this example at the drain) produces an output voltage Vout, which is coupled to antenna 350 through matching network 304. The power amplifier 310 is shown to have only a single MOS transistor stage for illustrative purposes only. Embodiments of the present disclosure may include multiple transistor stages, and in some embodiments, these stages are arranged in cascade (eg, stacked) outputs or other typical It should be understood that a power amplifier configuration may be included. The features and techniques of this disclosure are applicable to a wide range of amplifier topologies.

  In this example, programmable feedback circuit 321 has an input directly coupled to the drain of transistor 320 and an output directly coupled to the gate of transistor 320. In this case, the programmable feedback circuit 321 receives the control signal Ctrl, which is a logic signal. In other embodiments, Ctrl can be, for example, a continuous signal. Here, the programmable feedback circuit 321 can be set by the control circuit 301, which can determine, for example, the mode of operation of the wireless transmitter and the logic signal Ctrl for setting the programmable feedback circuit 321. Can be a baseband circuit, a processor, or other logic circuit. As one example, when the wireless transmitter is in ET mode, stability may not be as critical as the gain may be reduced when the power supply voltage is reduced for small signals. Thus, the control circuit 301 can set the programmable feedback circuit 321 to produce a lower negative feedback, for example, by increasing the feedback resistance between the drain and gate of the transistor 320. However, when the wireless transmitter is in APT mode, the small signal processed by the amplifier may require additional feedback to maintain stability. Thus, the control circuit 301 can set the programmable feedback circuit 321 to produce higher negative feedback, for example, by reducing the feedback resistance between the drain and gate of the transistor 320. Therefore, as described above, the RC circuit value in the APT mode may be smaller than the RC circuit value in the ET mode in order to increase the negative feedback from the drain to the gate. In one exemplary implementation described below, the corner frequency of a high pass filter from drain to gate increases negative feedback to stabilize the device. On the other hand, it is decreased in the APT mode. The control circuit 301 is a programmable feedback circuit, for example, to vary the feedback between the drain and gate to produce an optimized stability of the transistor 320 for a wide variety of other operating modes. A control signal may be sent to 321. Thus, the APT and ET modes described above are merely exemplary.

  [0025] FIG. 4 illustrates a wireless transmitter including a power amplifier, according to yet another embodiment. Similar to the example in FIG. 3, the control circuit 401 passed the envelope signal Ve and the matching circuit 403 to the gate of the transistor 420 (and possibly additional stages and circuitry in the signal path) for the ET mode. The preprocessor 402 may be configured to produce the input voltage Vin. In this example, power supply 423 produces a power supply voltage Vdd (t), which is coupled (through RFC 422) to both the drain of transistor 420 and the control input of programmable feedback circuit 421. Thus, in some embodiments, the drain to gate feedback of transistor 420 may be adjusted based on, for example, power supply voltage Vdd (t). As illustrated in more detail in the examples below, the change in power supply voltage is corresponding to transistor 420 in order to improve the stability of the power amplifier over a plurality of changing operating conditions with correspondingly different power supply voltage requirements. Can produce a change in feedback from the drain to the gate.

  [0026] FIG. 5A illustrates an exemplary programmable feedback circuit, according to one embodiment. In this example, the programmable feedback circuit includes a capacitor C500 and a variable (or programmable) resistor Rp501, which are configured in series. The first terminal of capacitor 500 is coupled to the drain (D) of the transistor, and the second terminal of capacitor 500 is coupled to the terminal of Rp501. The second terminal of Rp501 is coupled to the gate (G) of the transistor. The programmable feedback in this example forms a series RC circuit having a value set by the product of resistance and capacitance (Rp * C). A signal passing from the gate to the drain of the transistor will produce an inversion, so the feedback is negative to improve stability. Capacitor C removes DC from the feedback path. Feedback is controlled by resistance. As resistance increases, the feedback current is reduced, thereby reducing negative feedback. As resistance decreases, the feedback current increases, thereby increasing negative feedback, lowering gain, and stabilizing the circuit.

  [0027] FIG. 5B illustrates an exemplary programmable feedback circuit, according to another embodiment. Embodiments of a programmable feedback circuit may include a plurality of resistors, a plurality of switches (eg, MOS transistors configured as switches), and a capacitor configured between the drain and gate of the transistor. Similar to FIG. 5A, the first terminal of capacitor 500 is coupled to the drain of the transistor and the second terminal is coupled to a plurality of resistors and a plurality of switches in a parallel configuration, for example, The second terminal of capacitor 500 is coupled to the terminals of N switches SW1-SWN labeled 510-512. The other terminal of each switch 510-512 is coupled to the terminal of a particular resistor R1-RN502-504. The second terminal of each resistor 502-504 is coupled to the gate of the transistor. Thus, a plurality of series resistors and switches arranged in parallel can be programmed to change the resistance in series with capacitor 500. For example, when all switches SW1-SWN are opened, there is no drain-to-gate feedback. When SW1 is closed and the other switches are opened, R1 502 is in series with capacitor 500 to produce the first RC circuit value. When the additional switch is closed, the resistors in parallel arrangement function to reduce the total resistance in series with the capacitor 500, thereby reducing the RC circuit value. The switch can be opened and closed by logic signals from the control circuit, for example, as described above. This particular exemplary programmable feedback circuit embodiment includes resistors R1-RN having the same or different values, for example, to tune the feedback, depending on the needs of a particular design. Can be prepared.

  [0028] FIG. 5C illustrates an exemplary programmable feedback circuit, according to yet another embodiment. In this example, the terminal of capacitor 500 is coupled to the drain of the transistor, and another terminal of capacitor 500 is coupled to the first terminal of resistor R2 506 and the first terminal of switch SW2 514. The second terminal of resistor R2 506 is switch SW2 514 so that when SW2 is closed, SW2 is configured in parallel with R2 to create a short circuit around R2, thereby removing R2 from the feedback circuit. To the second terminal. The second terminal of R2 and the second terminal of SW2 are coupled to the first terminal of switch SW1 513. The second terminal of SW1 513 is coupled to the first terminal of resistor R1 505. The second terminal of resistor 505 is coupled to the gate of the transistor. Therefore, there is no feedback from the drain to the gate when SW1 is opened. When SW1 is closed and SW2 is opened, a series RC circuit is formed having an RC circuit value set by multiplying the sum of R1 and R2 by C (ie, (R1 + R2) * C). This configuration sets the highest RC circuit value with the lowest total amount of negative feedback from drain to gate and the highest feedback resistance. Negative feedback can be increased by closing SW2 and shorting R2, thereby reducing resistance in the feedback path from transistor drain to gate. The resulting RC circuit value is smaller than the RC circuit value when SW2 is opened, and negative feedback is increased to increase the stability of the circuit for this particular mode of operation. Various programmable feedback circuits in accordance with other embodiments include, for example, a large number of discrete feedback resistors (or continuous) available for programming corresponding to a wide variety of different modes of operation or transmission conditions. It should be understood that even a continuous range may be present.

[0029] FIG. 6A illustrates an exemplary programmable feedback circuit, according to another embodiment. In this example, the power supply voltage is used as a control input signal to change the resistance in the feedback path between the drain and gate of the transistor in the power amplifier circuit, thereby dynamically adjusting the stability of the circuit . In this example, a shaper circuit 623 receives a power supply voltage Vdd (t) for controlling the value of the variable resistor 621. The variable resistor 621 is configured in series with a capacitor 622 between the drain of the transistor 620 and the gate of the transistor 620. Shaper circuit 623 can provide various functional relations between Vdd (t) and resistance, for example, by receiving Vdd (t) and generating a control input signal that is a function of Vdd (t). Can be created. For example, in some embodiments, the output of the shaper circuit is such that the resistance is a function of Vdd ⁿ (t), an anth power of Vdd (eg, 1 <N <2 Vdd ⁿ (t)). It should be understood that the shaper circuit may use any other suitable function of Vdd (eg, an exponential function).

  [0030] FIG. 6B illustrates an exemplary programmable feedback circuit, according to yet another embodiment. This example illustrates one specific implementation example of using a power supply voltage as a control input signal to change the resistance in the feedback path between the drain and gate of a transistor in a power amplifier circuit. To do. For example, transistor 620 may receive input signal Vin through DC coupling capacitor C1 650, for example, at the gate, and produce output signal Vout through the drain. The power supply voltage is coupled to the drain of transistor 620 through an RF choke (RFC) 610. The programmable feedback circuit includes a capacitor 622 having a first terminal coupled to the drain of transistor 620 in this example. The second terminal of capacitor 622 is coupled to the first terminal of resistor 614. The second terminal of resistor 614 is coupled to the first terminal of resistor 613, and the second terminal of resistor 613 is coupled to the gate of transistor 620. The feedback resistance is varied using a transistor 612 configured in parallel with resistor 614 in this example. The first terminal of transistor 612 is coupled to the first terminal of resistor 614, and the second terminal of transistor 612 is coupled to the second terminal of resistor 614. The power supply voltage Vdd is coupled through gain stage 611 to the control terminal of transistor 612, which can translate the range of Vdd values into a corresponding range of values for controlling transistor 612. For example, when Vdd is high, the voltage at the control terminal of transistor 612 may turn on transistor 612 all the way, thereby shorting out resistor 614. Thus, when Vdd is high, the resistance in series with capacitor 622 is low and the RC circuit value is low, increasing the negative feedback from drain to gate to improve stability. However, as Vdd decreases, transistor 612 forms an increasingly resistive path in parallel with resistor 614. As the resistance in parallel with resistor 614 increases, the series resistance of the RC circuit increases and negative feedback decreases. When Vdd reaches some low threshold, transistor 612 is turned off and the maximum feedback resistance is obtained with an RC circuit value equal to the sum of resistor 613 and resistor 614 multiplied by capacitance 622, thereby Set the minimum negative feedback from the drain to the gate for the power amplifier gain stage.

  [0031] FIG. 7 illustrates an exemplary transistor feedback circuit configuration, according to another embodiment. Embodiments of the present disclosure may segment the transistors in the gain stage and provide separate RC feedback circuits around different segments as shown. For example, a particular transistor may be segmented into transistor segments 720A, 720B, and 720C (“segment”). Each segment may have a programmable RC feedback circuit coupled between the segment drain and the segment gate. For example, segment 720A includes, for example, resistor R1 711A and capacitor C1 710A configured in series between the drain of segment 720A and the gate of segment 720A. Similarly, segment 720B includes a resistor R2 711B and a capacitor C2 710B configured in series between the drain of segment 720B and the gate of segment 720B. Similarly, segment 720C includes a resistor R3 711C and a capacitor C3 710C configured in series between the drain of segment 720C and the gate of segment 720C. Segments 720A-C have gates, drains and sources coupled together to form a single transistor device. A separate programmable feedback circuit for a particular segment may improve uniformity across transistors in a power amplifier stage, for example.

  [0032] The above description illustrates various embodiments of the present disclosure, along with examples of how aspects of certain embodiments may be implemented. The above examples should not be considered to be the only embodiments, but are presented to illustrate the advantages and flexibility of certain embodiments as defined by the following claims. Based on the above disclosure and the following claims, other arrangements, embodiments, implementations and equivalents can be used without departing from the scope of this disclosure as defined by the claims. obtain.

[0032] The above description illustrates various embodiments of the present disclosure, along with examples of how aspects of certain embodiments may be implemented. The above examples should not be considered to be the only embodiments, but are presented to illustrate the advantages and flexibility of certain embodiments as defined by the following claims. Based on the above disclosure and the following claims, other arrangements, embodiments, implementations and equivalents can be used without departing from the scope of this disclosure as defined by the claims. obtain.
The invention described in the scope of claims at the beginning of the application of the present application will be added below.
[C1] A wireless transmitter,
A transistor comprising a source, a gate, and a drain, wherein the gate is coupled to an input signal to be transmitted, the drain is coupled to a power supply voltage, and to an antenna; Configured to amplify the input signal and produce an output signal,
A programmable feedback circuit having an input terminal coupled to the drain, an output terminal coupled to the gate, and a control input, wherein the programmable feedback circuit is a control signal received at the control input. Adjusting a series RC circuit between the gate and the drain of the transistor based on
Here, the programmable feedback circuit is configured to generate a first RC circuit value when the wireless transmitter is configured to generate a first power supply voltage to the drain of the transistor. The programmable feedback circuit changes negative feedback from the drain to the gate when the wireless transmitter is configured to produce a second power supply voltage to the drain of the transistor. In order to generate a second RC circuit value,
A wireless transmitter.
[C2] The first RC circuit value is generated when the wireless transmitter is configured to generate a variable power supply voltage corresponding to an envelope of the input signal, and the second RC circuit value is Generated when the wireless transmitter is configured to generate a constant power supply voltage to the drain of the transistor, the second RC circuit value increases negative feedback from the drain to the gate. Therefore, the wireless transmitter according to C1, which is smaller than the first RC circuit value.
[C3] The wireless transmitter according to C1, wherein the control signal is a logic signal.
[C4] The wireless transmitter according to C1, wherein the control signal is a continuous signal.
[C5] The wireless transmitter according to C1, wherein the control signal is the power supply voltage.
[C6] The programmable feedback circuit comprises a voltage shaping circuit having an input coupled to receive the power supply voltage and an output that produces a feedback resistor having a functional relationship to the power supply voltage. The listed wireless transmitter.
[C7] The transistor is a first transistor, wherein the programmable feedback circuit is:
A capacitor having a first terminal coupled to the drain of the first transistor and a second terminal;
A first resistor having a first terminal coupled to the second terminal of the capacitor; and a second terminal;
A second resistor having a first terminal coupled to the second terminal of the first resistor and a second terminal coupled to the gate of the first transistor;
Based on a first terminal coupled to the first terminal of the first resistor, a second terminal coupled to the second terminal of the first resistor, and the power supply voltage A second transistor having a control terminal coupled to a control voltage, wherein the series resistance between the drain and the gate of the second transistor is reduced, and accordingly, the first transistor The control voltage turns on the second transistor when the power supply voltage is increased to increase the negative feedback from the drain to the gate;
The wireless transmitter of C5, comprising:
[C8] The wireless transmitter of C1, wherein the programmable feedback circuit comprises a plurality of resistors, a plurality of switches, and a capacitor.
[C9] Each one of the plurality of resistors is in series with one of the plurality of switches, and the plurality of resistors are configured in parallel with each other and in series with the capacitor. A wireless transmitter according to C8.
[C10] The plurality of resistors and the plurality of switches are:
A first resistor having a first terminal coupled to the first terminal of the capacitor and a second terminal;
A first switch having a first terminal coupled to the second terminal of the first resistor and a second terminal coupled to the first terminal of the first resistor; ,
A second switch having a first terminal coupled to the second terminal of the first resistor and a second terminal;
A second resistor having a first terminal coupled to the second terminal of the second switch and a second terminal coupled to the gate of the transistor;
With
Wherein the second terminal of the capacitor is coupled to the drain of the transistor.
[C11] The transistor includes a plurality of segments each including a source, a gate, and a drain, wherein each segment includes a resistor configured in series between the drain and the gate of the segment, and The wireless transmitter of C1, comprising a capacitor.
[C12] The wireless transmitter of C1, wherein the drain is coupled to the antenna through one or more additional gain stages.
[C13] method,
Receiving an input signal at the gate of the transistor, the transistor comprising a source, a gate, and a drain, wherein the drain is coupled to a power supply voltage and to an antenna; the transistor amplifies the input signal; Configured to produce an output signal,
The portion of the output signal from the drain of the transistor is passed through a programmable feedback circuit having an input terminal coupled to the drain, an output terminal coupled to the gate, and a control input. And wherein the programmable feedback circuit adjusts a series RC circuit between the gate and the drain of the transistor based on a control signal received at the control input. To
Wherein the programmable feedback circuit is configured to generate a first RC circuit value when the wireless transmitter is configured to generate a first power supply voltage to the drain of the transistor; The programmable feedback circuit varies the negative feedback from the drain to the gate when the wireless transmitter is configured to produce a second power supply voltage to the drain of the transistor. Configured to produce a second RC circuit value;
A method comprising:
[C14] The first RC circuit value is generated when the wireless transmitter is configured to generate a variable power supply voltage corresponding to an envelope of the input signal, and the second RC circuit value is Generated when the wireless transmitter is configured to generate a constant power supply voltage to the drain of the transistor, the second RC circuit value increases negative feedback from the drain to the gate. Therefore, the method of C13, wherein the method is smaller than the first RC circuit value.
[C15] The method according to C13, wherein the control signal is a logic signal.
[C16] The method according to C13, wherein the control signal is a continuous signal.
[C17] The method according to C13, wherein the control signal is the power supply voltage.
[C18] A wireless transmitter,
A transistor comprising a source, a gate, and a drain, wherein the gate is coupled to an input signal to be transmitted, the drain is coupled to a power supply voltage, and to an antenna; Configured to amplify an input signal and produce an output signal at the drain;
Means for adjusting negative feedback from the drain to the gate of the transistor based on a control signal;
Wherein the means for adjusting negative feedback is configured such that when the wireless transmitter is configured to produce a variable power supply voltage corresponding to an envelope of the input signal to the drain of the transistor. Configured to produce a RC circuit value of 1 and the means for adjusting negative feedback is configured when the wireless transmitter is configured to produce a constant power supply voltage to the drain of the transistor; Configured to produce a second RC circuit value that is less than the first RC circuit value to increase negative feedback from the drain to the gate;
A wireless transmitter.

Claims (18)

A wireless transmitter,
A transistor comprising a source, a gate, and a drain, wherein the gate is coupled to an input signal to be transmitted, the drain is coupled to a power supply voltage, and to an antenna; Configured to amplify the input signal and produce an output signal,
A programmable feedback circuit having an input terminal coupled to the drain, an output terminal coupled to the gate, and a control input, wherein the programmable feedback circuit is a control signal received at the control input. Adjusting a series RC circuit between the gate and the drain of the transistor based on
Here, the programmable feedback circuit is configured to generate a first RC circuit value when the wireless transmitter is configured to generate a first power supply voltage to the drain of the transistor. The programmable feedback circuit changes negative feedback from the drain to the gate when the wireless transmitter is configured to produce a second power supply voltage to the drain of the transistor. In order to generate a second RC circuit value,
A wireless transmitter.   The first RC circuit value is generated when the wireless transmitter is configured to generate a variable power supply voltage corresponding to an envelope of the input signal, and the second RC circuit value is generated by the wireless transmission. Generated when the machine is configured to generate a constant power supply voltage to the drain of the transistor, the second RC circuit value is increased to increase negative feedback from the drain to the gate, The wireless transmitter of claim 1, wherein the wireless transmitter is less than the first RC circuit value.   The wireless transmitter of claim 1, wherein the control signal is a logic signal.   The wireless transmitter of claim 1, wherein the control signal is a continuous signal.   The wireless transmitter of claim 1, wherein the control signal is the power supply voltage.   6. The voltage feedback circuit of claim 5, wherein the programmable feedback circuit comprises a voltage shaping circuit having an input coupled to receive the power supply voltage and an output that produces a feedback resistor having a functional relationship to the power supply voltage. Wireless transmitter. The transistor is a first transistor, where the programmable feedback circuit is:
A capacitor having a first terminal coupled to the drain of the first transistor and a second terminal;
A first resistor having a first terminal coupled to the second terminal of the capacitor; and a second terminal;
A second resistor having a first terminal coupled to the second terminal of the first resistor and a second terminal coupled to the gate of the first transistor;
Based on a first terminal coupled to the first terminal of the first resistor, a second terminal coupled to the second terminal of the first resistor, and the power supply voltage A second transistor having a control terminal coupled to a control voltage, wherein the series resistance between the drain and the gate of the second transistor is reduced, and accordingly, the first transistor The control voltage turns on the second transistor when the power supply voltage is increased to increase the negative feedback from the drain to the gate;
The wireless transmitter of claim 5, comprising:   The wireless transmitter of claim 1, wherein the programmable feedback circuit comprises a plurality of resistors, a plurality of switches, and a capacitor.   Each one of the plurality of resistors is in series with one of the plurality of switches, and the plurality of resistors are configured in parallel with each other and in series with the capacitor. 9. The wireless transmitter according to 8. The plurality of resistors and the plurality of switches are:
A first resistor having a first terminal coupled to the first terminal of the capacitor and a second terminal;
A first switch having a first terminal coupled to the second terminal of the first resistor and a second terminal coupled to the first terminal of the first resistor; ,
A second switch having a first terminal coupled to the second terminal of the first resistor and a second terminal;
A second resistor having a first terminal coupled to the second terminal of the second switch and a second terminal coupled to the gate of the transistor;
With
9. The wireless transmitter of claim 8, wherein a second terminal of the capacitor is coupled to the drain of the transistor.   The transistor comprises a plurality of segments each comprising a source, a gate, and a drain, wherein each segment comprises a resistor and a capacitor configured in series between the drain and the gate of the segment. The wireless transmitter of claim 1.   The wireless transmitter of claim 1, wherein the drain is coupled to the antenna through one or more additional gain stages. A method,
Receiving an input signal at the gate of the transistor, the transistor comprising a source, a gate, and a drain, wherein the drain is coupled to a power supply voltage and to an antenna; the transistor amplifies the input signal; Configured to produce an output signal,
The portion of the output signal from the drain of the transistor is passed through a programmable feedback circuit having an input terminal coupled to the drain, an output terminal coupled to the gate, and a control input. And wherein the programmable feedback circuit adjusts a series RC circuit between the gate and the drain of the transistor based on a control signal received at the control input. To
Wherein the programmable feedback circuit is configured to generate a first RC circuit value when the wireless transmitter is configured to generate a first power supply voltage to the drain of the transistor; The programmable feedback circuit varies the negative feedback from the drain to the gate when the wireless transmitter is configured to produce a second power supply voltage to the drain of the transistor. Configured to produce a second RC circuit value;
A method comprising:   The first RC circuit value is generated when the wireless transmitter is configured to generate a variable power supply voltage corresponding to an envelope of the input signal, and the second RC circuit value is generated by the wireless transmission. Generated when the machine is configured to generate a constant power supply voltage to the drain of the transistor, the second RC circuit value is increased to increase negative feedback from the drain to the gate, The method of claim 13, wherein the method is less than the first RC circuit value.   The method of claim 13, wherein the control signal is a logic signal.   The method of claim 13, wherein the control signal is a continuous signal.   The method of claim 13, wherein the control signal is the power supply voltage. A wireless transmitter,
A transistor comprising a source, a gate, and a drain, wherein the gate is coupled to an input signal to be transmitted, the drain is coupled to a power supply voltage, and to an antenna; Configured to amplify an input signal and produce an output signal at the drain;
Means for adjusting negative feedback from the drain to the gate of the transistor based on a control signal;
Wherein the means for adjusting negative feedback is configured such that when the wireless transmitter is configured to produce a variable power supply voltage corresponding to an envelope of the input signal to the drain of the transistor. Configured to produce a RC circuit value of 1 and the means for adjusting negative feedback is configured when the wireless transmitter is configured to produce a constant power supply voltage to the drain of the transistor; Configured to produce a second RC circuit value that is less than the first RC circuit value to increase negative feedback from the drain to the gate;
A wireless transmitter.

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